Gonadotropin expression, pituitary and plasma levels in the reproductive cycle of wild and captive-reared greater amberjack (Seriola dumerili).

We compared the endocrine status of the pituitary-gonad axis of wild and captive-reared greater amberjack (Seriola dumerili) during the reproductive cycle (April - July), reporting on the expression and release of the two gonadotropins for the first time in the Mediterranean Sea. Ovaries from wild females were characterized histologically as DEVELOPING in early May and SPAWNING capable in late May-July, the latter having a 3 to 4-fold higher gonadosomatic index (GSI). SPAWNING capable wild females exhibited an increase in pituitary follicle stimulating hormone (Fsh) content, plasma testosterone (T) and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P), while almost a 10-fold increase was observed in pituitary luteinizing hormone (Lh) content.

Evaluation of Flathead Grey Mullets () Immunization and Long-Term Protection against Infection Using Three Different Vaccine Preparations.

In recent years, flathead grey mullets () cultured in Eilat (Israel) have been highly affected by , showing neurological signs such as uncoordinated circular swimming followed by high mortality rates. Despite the advances in and different approaches to control vibriosis associated with , including commercial vaccines, most of them have not succeeded in long-term protection. In this study, we evaluated the effectiveness, long-term protection, and antibody production of three vaccine preparations: heat-killed bacteria (HKB), membrane proteins denaturation (BME PROT), and internal proteins (INT PROT) developed specifically against for grey mullets.

A novel c.1759T>G variant in follicle-stimulating hormone-receptor gene is concordant with male determination in the flathead grey mullet (Mugil cephalus).

Various master key regulators (MKRs) that control a binary switch of sex determination (SD) have been found in fish; these provide an excellent model for the study of vertebrate genetic SD. The SD region in flathead grey mullet has been previously mapped to a 1 Mbp region harboring 27 genes, of which one is follicle-stimulating hormone receptor (fshr). Although this gene is involved in gonad differentiation and function, it has not been considered as an MKR of SD.

The effect of algal turbidity on larval performance and the ontogeny of digestive enzymes in the grey mullet (Mugil cephalus).

A study comprised of two trials determined the effects of water turbidity produced by live microalgae and inert clay particles on the larval rearing of grey mullet (Mugil cephalus). Trial 1 evaluated the effect of microalgae produced water turbidity on grey mullet larval performance and digestive tract (DT) enzyme ontogeny. Two microalgae (Nannochloropsis oculata and Isochrysis galbana) water turbidity levels (0.

In vitro effect of cortisol and urotensin I on arginine vasotocin and isotocin secretion from pituitary cells of gilthead sea bream Sparus aurata.

This study aimed at determining whether in vitro secretion of two neuropeptides, arginine vasotocin (AVT) and isotocin (IT), from pituitary cells of gilthead sea bream Sparus aurata was affected by cortisol and urotensin (UI). Pituitary cells were exposed to 1·4 × 10(-8) , 1·4 × 10(-7) and 0·4 × 10(-6)  M cortisol and 10(-12) , 10(-10) and 10(-8)  M UI for 6, 24 and 48 h, respectively. AVT and IT contents were determined in the culture media by high-performance liquid chromatography (HPLC).